Until now, there had been known a shoulder bag which has not only a detachable shoulder belt but also a grip. The shoulder bag is used as a brief-case or a grip-sack when the shoulder belt is detached, and is used as a shoulder bag when the shoulder belt is attached. Such shoulder belt for a shoulder bag is usually fastened to a bag body, for example, as shown in FIG. 10. That is to say, a belt 101 is jointed to a fastening hook 102 at an end thereof, and is connected to a bag body 103 by hooking the hook 102 with a ring-like connecting link 104 which is attached to an end of the bag body 103. The connecting hook 102 has a ring portion 105 to pass an end of the belt 101, a hook body 106 which is rotatably attached to or fixed to the ring portion 105, and a closing piece 107 to close an opening of the hook body 106 so that the hook body 106 does not come out of the connecting link 104. The closing piece 107 can elastically yield to open the hook body 106.
The above-mentioned connecting hook 102 can be easily jointed to the connecting link 104 by abutting the closing piece 107 against the connecting link 104. That is to say, when the hook 102 is pressed to the link 104, the closing piece 107 yields to open the hook body 104, and the link 104 comes into the hook body 104. However, when the hook 102 is detached from the link 104, the user must move the hook body 14 so that the link 104 comes to the curved port ion or free end of the hook body 14, for example, by pulling the hook body 14. Then, the user must push the closing piece 107 to yield it inside in order to obtain a gap through which the link 104 passes. Therefore, the detaching is very troublesome for the user, and in the actual case, after the belt is once attached, the user uses the bag with remaining jointed with the belt. As a result, such bag is used as a shoulder bag only.